The clinical patterns of myalgia in children with familial Mediterranean fever

Objectives: To study the frequency and clinical patterns of myalgia in a de fined group of children with familial Mediterranean fever (FMF). Methods: A prospective 4-year (September 1995-September 1999) study of chil dren with FMF seen in the pediatric FMF clinic of Jordan University teachin g hospital. Diagnosis of FMF was made according to published criteria. Once the diagnosis of FMF and myalgia was made, details about myalgia were coll ected by interview with the child and his/her parents and entered into a sp ecial study form. Results: Of 264 children with FMF seen over the study period, 65 (25%) deve loped myalgia. Three clinical patterns of myalgia were identified: the spon taneous pattern, the exercise-induced pattern, and the protracted febrile m yalgia syndrome (PFMS), seen in 8%, 81%, and 11% of patients, respectively. The three patterns differed in the severity of pain, height of fever, and duration of the episode. In 33 children with the exercise-induced myalgia, in which response to colchicine could be reliably assessed, a favorable res ponse was achieved in 97%. Three children with the PFMS had a dramatic resp onse to corticosteroids. Conclusions: Myalgia in children with FMF is common and can follow three di fferent clinical patterns. Copyright (C) 2000 by W.B. Saunders Company.